Well, 50 miles later, the CEL is off. I took the dpfe off, shook it on my hand, and had a little bit of water come out (only a few small drops), left it out in the sun for an hour, and put it back on. Full diagnostic states that the dpfe is fully operational (downstream and upstream, or the reference and pressure lines). As for the pinging, I haven't had that, yet...but it does seem to get bogged down every once in a while. Then again, it may be just because I short shift now and then. The car idles much more smoothly now and seems to be more responsive. The O2 sensors are the same (.03-.9 volts), but the downstream switches much slower than the upstreams now. I came to the conclusion that they were switching at the same rate since the engine was in such a rich condition (short term fuel was at 25%!!!) to compensate for the so called lean condition.
I'll wait a few more days and report back, CEL or not. Thanks for all the help guys (and those on the Windstar forum) and hopefully this will help some of you out as well!
Sean
